info about login control..

protected void ctlLogin_Authenticate(object sender, AuthenticateEventArgs e)
    {
        bool Authenticated = false;

        Authenticated = UserAuthenticate(ctlLogin.UserName, ctlLogin.Password);
        e.Authenticated = Authenticated;
       if (Authenticated == true)
        {


            Response.Redirect("information1.aspx");

       }
    }

    private bool UserAuthenticate(string UserName, string Password) what this fuction do?
    {
       bool boolReturnValue = false;  what this line do?  
        //--------------------------------
        //Check UserID From Config File

            //--------------------------------
            dt = new DataTable();
            SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Users\omar\Documents\Visual Studio 2005\WebSites\Project1\App_Data\Database.mdf;Integrated Security=True;User Instance=True");
            string chkUser = "Select * FROM [User] where Email='" + UserName + "' AND Password='" + Password + "'";
            dt = dbClass.ConnectDataBaseReturnDT(chkUser);
            if (dt.Rows.Count > 0)
            {
                boolReturnValue = true; what this line do?
                Session["Id"] = dt.Rows[0]["Id"].ToString();
               string que = "UPDATE [User] SET LastLogin = GETDATE() where Id=" + Session["Id"].ToString();
              //  DateTime registerdate = (DateTime)dt.Rows[0]["RegisterDate"];
               // string que1 = "UPDATE [User] SET RegisterDate = GETDATE() where Id=" + Session["UserId"].ToString();
               dbClass.ConnectDataBaseToInsert(que);
                //dbClass.ConnectDataBaseToInsert(que1);
           }
           return boolReturnValue; what this line do?



    }